diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..ef58455
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,5 @@
+/nbproject/private/
+/build
+/avrrfm.elf
+/avrrfm.hex
+/avrrfm.lst
diff --git a/CODE_OF_CONDUCT.md b/CODE_OF_CONDUCT.md
new file mode 100644
index 0000000..1ecc37c
--- /dev/null
+++ b/CODE_OF_CONDUCT.md
@@ -0,0 +1,128 @@
+# Contributor Covenant Code of Conduct
+
+## Our Pledge
+
+We as members, contributors, and leaders pledge to make participation in our
+community a harassment-free experience for everyone, regardless of age, body
+size, visible or invisible disability, ethnicity, sex characteristics, gender
+identity and expression, level of experience, education, socio-economic status,
+nationality, personal appearance, race, religion, or sexual identity
+and orientation.
+
+We pledge to act and interact in ways that contribute to an open, welcoming,
+diverse, inclusive, and healthy community.
+
+## Our Standards
+
+Examples of behavior that contributes to a positive environment for our
+community include:
+
+* Demonstrating empathy and kindness toward other people
+* Being respectful of differing opinions, viewpoints, and experiences
+* Giving and gracefully accepting constructive feedback
+* Accepting responsibility and apologizing to those affected by our mistakes,
+ and learning from the experience
+* Focusing on what is best not just for us as individuals, but for the
+ overall community
+
+Examples of unacceptable behavior include:
+
+* The use of sexualized language or imagery, and sexual attention or
+ advances of any kind
+* Trolling, insulting or derogatory comments, and personal or political attacks
+* Public or private harassment
+* Publishing others' private information, such as a physical or email
+ address, without their explicit permission
+* Other conduct which could reasonably be considered inappropriate in a
+ professional setting
+
+## Enforcement Responsibilities
+
+Community leaders are responsible for clarifying and enforcing our standards of
+acceptable behavior and will take appropriate and fair corrective action in
+response to any behavior that they deem inappropriate, threatening, offensive,
+or harmful.
+
+Community leaders have the right and responsibility to remove, edit, or reject
+comments, commits, code, wiki edits, issues, and other contributions that are
+not aligned to this Code of Conduct, and will communicate reasons for moderation
+decisions when appropriate.
+
+## Scope
+
+This Code of Conduct applies within all community spaces, and also applies when
+an individual is officially representing the community in public spaces.
+Examples of representing our community include using an official e-mail address,
+posting via an official social media account, or acting as an appointed
+representative at an online or offline event.
+
+## Enforcement
+
+Instances of abusive, harassing, or otherwise unacceptable behavior may be
+reported to the community leaders responsible for enforcement at
+dode@luniks.net.
+All complaints will be reviewed and investigated promptly and fairly.
+
+All community leaders are obligated to respect the privacy and security of the
+reporter of any incident.
+
+## Enforcement Guidelines
+
+Community leaders will follow these Community Impact Guidelines in determining
+the consequences for any action they deem in violation of this Code of Conduct:
+
+### 1. Correction
+
+**Community Impact**: Use of inappropriate language or other behavior deemed
+unprofessional or unwelcome in the community.
+
+**Consequence**: A private, written warning from community leaders, providing
+clarity around the nature of the violation and an explanation of why the
+behavior was inappropriate. A public apology may be requested.
+
+### 2. Warning
+
+**Community Impact**: A violation through a single incident or series
+of actions.
+
+**Consequence**: A warning with consequences for continued behavior. No
+interaction with the people involved, including unsolicited interaction with
+those enforcing the Code of Conduct, for a specified period of time. This
+includes avoiding interactions in community spaces as well as external channels
+like social media. Violating these terms may lead to a temporary or
+permanent ban.
+
+### 3. Temporary Ban
+
+**Community Impact**: A serious violation of community standards, including
+sustained inappropriate behavior.
+
+**Consequence**: A temporary ban from any sort of interaction or public
+communication with the community for a specified period of time. No public or
+private interaction with the people involved, including unsolicited interaction
+with those enforcing the Code of Conduct, is allowed during this period.
+Violating these terms may lead to a permanent ban.
+
+### 4. Permanent Ban
+
+**Community Impact**: Demonstrating a pattern of violation of community
+standards, including sustained inappropriate behavior, harassment of an
+individual, or aggression toward or disparagement of classes of individuals.
+
+**Consequence**: A permanent ban from any sort of public interaction within
+the community.
+
+## Attribution
+
+This Code of Conduct is adapted from the [Contributor Covenant][homepage],
+version 2.0, available at
+https://www.contributor-covenant.org/version/2/0/code_of_conduct.html.
+
+Community Impact Guidelines were inspired by [Mozilla's code of conduct
+enforcement ladder](https://github.com/mozilla/diversity).
+
+[homepage]: https://www.contributor-covenant.org
+
+For answers to common questions about this code of conduct, see the FAQ at
+https://www.contributor-covenant.org/faq. Translations are available at
+https://www.contributor-covenant.org/translations.
diff --git a/LICENSE b/LICENSE
new file mode 100644
index 0000000..94a9ed0
--- /dev/null
+++ b/LICENSE
@@ -0,0 +1,674 @@
+ GNU GENERAL PUBLIC LICENSE
+ Version 3, 29 June 2007
+
+ Copyright (C) 2007 Free Software Foundation, Inc.
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+ Preamble
+
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+software and other kinds of works.
+
+ The licenses for most software and other practical works are designed
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+share and change all versions of a program--to make sure it remains free
+software for all its users. We, the Free Software Foundation, use the
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+any other work released this way by its authors. You can apply it to
+your programs, too.
+
+ When we speak of free software, we are referring to freedom, not
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+
+ A patent license is "discriminatory" if it does not include within
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+or that patent license was granted, prior to 28 March 2007.
+
+ Nothing in this License shall be construed as excluding or limiting
+any implied license or other defenses to infringement that may
+otherwise be available to you under applicable patent law.
+
+ 12. No Surrender of Others' Freedom.
+
+ If conditions are imposed on you (whether by court order, agreement or
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+excuse you from the conditions of this License. If you cannot convey a
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+not convey it at all. For example, if you agree to terms that obligate you
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+the Program, the only way you could satisfy both those terms and this
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+
+ 13. Use with the GNU Affero General Public License.
+
+ Notwithstanding any other provision of this License, you have
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+combination as such.
+
+ 14. Revised Versions of this License.
+
+ The Free Software Foundation may publish revised and/or new versions of
+the GNU General Public License from time to time. Such new versions will
+be similar in spirit to the present version, but may differ in detail to
+address new problems or concerns.
+
+ Each version is given a distinguishing version number. If the
+Program specifies that a certain numbered version of the GNU General
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+option of following the terms and conditions either of that numbered
+version or of any later version published by the Free Software
+Foundation. If the Program does not specify a version number of the
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+
+ If the Program specifies that a proxy can decide which future
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+public statement of acceptance of a version permanently authorizes you
+to choose that version for the Program.
+
+ Later license versions may give you additional or different
+permissions. However, no additional obligations are imposed on any
+author or copyright holder as a result of your choosing to follow a
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+
+ 15. Disclaimer of Warranty.
+
+ THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
+APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
+HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY
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+ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
+
+ 16. Limitation of Liability.
+
+ IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
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+THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
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+USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
+DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
+PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
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+SUCH DAMAGES.
+
+ 17. Interpretation of Sections 15 and 16.
+
+ If the disclaimer of warranty and limitation of liability provided
+above cannot be given local legal effect according to their terms,
+reviewing courts shall apply local law that most closely approximates
+an absolute waiver of all civil liability in connection with the
+Program, unless a warranty or assumption of liability accompanies a
+copy of the Program in return for a fee.
+
+ END OF TERMS AND CONDITIONS
+
+ How to Apply These Terms to Your New Programs
+
+ If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+ To do so, attach the following notices to the program. It is safest
+to attach them to the start of each source file to most effectively
+state the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+
+ Copyright (C)
+
+ This program is free software: you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation, either version 3 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program. If not, see .
+
+Also add information on how to contact you by electronic and paper mail.
+
+ If the program does terminal interaction, make it output a short
+notice like this when it starts in an interactive mode:
+
+ Copyright (C)
+ This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
+ This is free software, and you are welcome to redistribute it
+ under certain conditions; type `show c' for details.
+
+The hypothetical commands `show w' and `show c' should show the appropriate
+parts of the General Public License. Of course, your program's commands
+might be different; for a GUI interface, you would use an "about box".
+
+ You should also get your employer (if you work as a programmer) or school,
+if any, to sign a "copyright disclaimer" for the program, if necessary.
+For more information on this, and how to apply and follow the GNU GPL, see
+.
+
+ The GNU General Public License does not permit incorporating your program
+into proprietary programs. If your program is a subroutine library, you
+may consider it more useful to permit linking proprietary applications with
+the library. If this is what you want to do, use the GNU Lesser General
+Public License instead of this License. But first, please read
+.
diff --git a/Makefile b/Makefile
new file mode 100644
index 0000000..54c2455
--- /dev/null
+++ b/Makefile
@@ -0,0 +1,37 @@
+# Makefile to build librfm
+
+MCU = atmega328p
+F_CPU = 8000000
+
+MAIN = librfm.c
+
+CC = avr-gcc
+
+CFLAGS = -mmcu=$(MCU) -DF_CPU=$(F_CPU)UL
+CFLAGS += -O2 -I.
+CFLAGS += -funsigned-char -funsigned-bitfields -fpack-struct -fshort-enums
+CFLAGS += -Wall -Wstrict-prototypes
+CFLAGS += -g -ggdb
+CFLAGS += -ffunction-sections -fdata-sections -Wl,--gc-sections -mrelax
+CFLAGS += -std=gnu99
+# https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105523
+# CFLAGS += --param=min-pagesize=0
+
+TARGET = $(strip $(basename $(MAIN)))
+SRC += $(TARGET).c
+
+OBJ = $(SRC:.c=.o)
+OBJ = $(SRC:.S=.o)
+
+$(TARGET).elf: librfm.h pins.h spi.h types.h utils.h Makefile
+
+all: $(TARGET).elf
+
+%.elf: $(SRC)
+ $(CC) $(CFLAGS) $(SRC) --output $@
+
+clean:
+ rm -f $(TARGET).elf $(TARGET).hex $(TARGET).obj \
+ $(TARGET).o $(TARGET).d $(TARGET).eep $(TARGET).lst \
+ $(TARGET).lss $(TARGET).sym $(TARGET).map $(TARGET)~ \
+ $(TARGET).eeprom
diff --git a/README.md b/README.md
new file mode 100644
index 0000000..23ceb60
--- /dev/null
+++ b/README.md
@@ -0,0 +1,41 @@
+# AVRRFM
+
+## About
+
+Experimental library project to drive an RFM69HCW radio module with plain
+avr-libc.
+
+This is work in progress. Simple Tx-Rx with response is working so far.
+
+## Build
+
+ avr-gcc -mmcu=atmega328p -DF_CPU=8000000UL -O2 -I. -funsigned-char -funsigned-bitfields -fpack-struct -fshort-enums -Wall -Wstrict-prototypes -g -ggdb -ffunction-sections -fdata-sections -Wl,--gc-sections -mrelax -std=gnu99 -MMD -MP -MFlibrfm.d -MTlibrfm.d librfm.c -c -olibrfm.o
+
+ avr-ar rcs librfm.a librfm.o
+
+## Range
+
+Setting `RegPaLevel` to `0x5f`, which gives +13 dBm with `PA1`, indoor range is
+very good and in an actual "field" test, packet reception was still reliable
+with an RSSI of about -90 dBm at about 2.2 km distance - with simple wire
+antennas. What would be the range with +20 dBm and decent antennas?
+
+
+
+## Susceptibility to Temperature Changes
+
+With the default frequency deviation of 5 kHz and receiver bandwidth of
+10.4 kHz, packet transmission is very unreliable and fails completely for me;
+when the temperature of the transmitter is below 10°C and above 40°C, while
+the receiver temperature is at 20°C. The receiver does not seem to be prone to
+temperature changes.
+Increasing frequency deviation to 10 kHz and receiver bandwidth to 20.8 kHz,
+temperature susceptibility is eliminated; when testing with transmitter
+temperature from -20°C to 50°C, packet transmission is perfectly reliable.
+
+Frequency Deviation = 10 kHz (transmitter)
+`RegFdevMsb` = `0x00`
+`RegFdevLsb` = `0xa4`
+
+Receiver Bandwidth = 20.8 kHz
+`RegRxBw` = `0x54`
diff --git a/librfm.a b/librfm.a
new file mode 100644
index 0000000..180e8a0
--- /dev/null
+++ b/librfm.a
Binary files differ
diff --git a/librfm.c b/librfm.c
new file mode 100644
index 0000000..773a80b
--- /dev/null
+++ b/librfm.c
@@ -0,0 +1,328 @@
+/*
+ * File: rfm69.c
+ * Author: torsten.roemer@luniks.net
+ *
+ * Created on 28. Januar 2025, 19:57
+ */
+
+#include "librfm.h"
+#include "types.h"
+
+static volatile uint8_t irqFlags1 = 0;
+static volatile uint8_t irqFlags2 = 0;
+static volatile uint8_t timeoutInts = 0;
+static volatile bool timeoutEnabled = false;
+
+/**
+ * Selects the radio to talk to via SPI.
+ */
+static void spiSel(void) {
+ PORT_RFM &= ~(1 << PIN_RCS);
+}
+
+/**
+ * Deselects the radio to talk to via SPI.
+ */
+static void spiDes(void) {
+ PORT_RFM |= (1 << PIN_RCS);
+}
+
+/**
+ * Writes the given value to the given register.
+ *
+ * @param reg
+ * @param value
+ */
+static void regWrite(uint8_t reg, uint8_t value) {
+ spiSel();
+ transmit(reg | 0x80);
+ transmit(value);
+ spiDes();
+}
+
+/**
+ * Reads and returns the value of the given register.
+ *
+ * @param reg
+ * @return value
+ */
+static uint8_t regRead(uint8_t reg) {
+ spiSel();
+ transmit(reg & 0x7f);
+ uint8_t value = transmit(0x00);
+ spiDes();
+
+ return value;
+}
+
+/**
+ * Sets the module to the given operating mode.
+ */
+static void setMode(uint8_t mode) {
+ regWrite(OP_MODE, (regRead(OP_MODE) & ~MASK_MODE) | (mode & MASK_MODE));
+}
+
+/**
+ * Clears the IRQ flags read from the module.
+ */
+static void clearIrqFlags(void) {
+ irqFlags1 = 0;
+ irqFlags2 = 0;
+}
+
+/**
+ * Enables timeout (sets timeout interrupt flag on expiration).
+ *
+ * @param enable
+ */
+static void timeoutEnable(bool enable) {
+ timeoutEnabled = enable;
+ if (!enable) timeoutInts = 0;
+}
+
+/**
+ * Times out the current operation.
+ */
+static void timeout(void) {
+ irqFlags1 |= (1 << 2);
+}
+
+void initRadio(uint64_t freq, uint8_t node) {
+ // wait a bit after power on
+ _delay_ms(10);
+
+ // pull reset LOW to turn on the module
+ PORT_RFM &= ~(1 << PIN_RRST);
+
+ _delay_ms(5);
+
+ // uint8_t version = regRead(0x10);
+ // printString("Version: ");
+ // printHex(version);
+
+ // packet mode, FSK modulation, no shaping (default)
+ regWrite(DATA_MOD, 0x00);
+
+ // bit rate 9.6 kBit/s
+ // regWrite(BITRATE_MSB, 0x0d);
+ // regWrite(BITRATE_LSB, 0x05);
+
+ // frequency deviation (default 5 kHz) - increasing to 10 kHz
+ // completely removes susceptibility to temperature changes
+ // RX_BW must be increased accordingly
+ regWrite(FDEV_MSB, 0x00);
+ regWrite(FDEV_LSB, 0xa4);
+
+ // RC calibration, automatically done at device power-up
+ // regWrite(OSC1, 0x80);
+ // do { } while (!(regRead(OSC1) & 0x40));
+
+ // PA level (default +13 dBm with PA0, yields very weak output power, why?)
+ // regWrite(PA_LEVEL, 0x9f);
+ // +13 dBm on PA1, yields the expected output power
+ regWrite(PA_LEVEL, 0x5f);
+ // +17 dBm - doesn't seem to work just like that?
+ // regWrite(PA_LEVEL, 0x7f);
+
+ // LNA 200 Ohm, gain AGC (default)
+ regWrite(LNA, 0x88);
+ // LNA 50 Ohm, gain AGC
+ // regWrite(LNA, 0x08);
+
+ // LNA high sensitivity mode
+ // regWrite(TEST_LNA, 0x2d);
+
+ // freq of DC offset canceller and channel filter bandwith (default 10.4 kHz)
+ // increasing to 20.8 kHz in connection with setting FDEV_*SB to 10 kHz
+ // completely removes susceptibility to temperature changes
+ regWrite(RX_BW, 0x54);
+
+ // RX_BW during AFC (default 0x8b)
+ regWrite(AFC_BW, 0x54);
+
+ // AFC auto on
+ // regWrite(AFC_FEI, 0x04);
+
+ // RSSI threshold (default, POR 0xff)
+ regWrite(RSSI_THRESH, 0xe4);
+
+ // Preamble size
+ regWrite(PREAMB_MSB, 0x00);
+ regWrite(PREAMB_LSB, 0x0f);
+
+ // turn off CLKOUT (not used)
+ regWrite(DIO_MAP2, 0x07);
+
+ // set the carrier frequency
+ uint32_t frf = freq * 100000000000ULL / F_STEP;
+ regWrite(FRF_MSB, frf >> 16);
+ regWrite(FRF_MID, frf >> 8);
+ regWrite(FRF_LSB, frf >> 0);
+
+ // enable sync word generation and detection, FIFO fill on sync address,
+ // 4 bytes sync word, tolerate 3 bit errors
+ regWrite(SYNC_CONF, 0x9b);
+
+ // just set all sync word values to some really creative value
+ regWrite(SYNC_VAL1, 0x2f);
+ regWrite(SYNC_VAL2, 0x30);
+ regWrite(SYNC_VAL3, 0x31);
+ regWrite(SYNC_VAL4, 0x32);
+ regWrite(SYNC_VAL5, 0x33);
+ regWrite(SYNC_VAL6, 0x34);
+ regWrite(SYNC_VAL7, 0x35);
+ regWrite(SYNC_VAL8, 0x36);
+
+ // variable payload length, crc on, no address matching
+ // regWrite(PCK_CFG1, 0x90);
+ // match broadcast or node address
+ // regWrite(PCK_CFG1, 0x94);
+ // + CrcAutoClearOff
+ regWrite(PCK_CFG1, 0x9c);
+
+ // disable automatic RX restart
+ regWrite(PCK_CFG2, 0x00);
+
+ // node and broadcast address
+ regWrite(NODE_ADDR, node);
+ regWrite(CAST_ADDR, CAST_ADDRESS);
+
+ // set TX start condition to "at least one byte in FIFO"
+ regWrite(FIFO_THRESH, 0x8f);
+
+ // Fading Margin Improvement, improved margin, use if AfcLowBetaOn=0
+ regWrite(TEST_DAGC, 0x30);
+
+ // printString("Radio init done\r\n");
+}
+
+/**
+ * Reads interrupt flags when a radio interrupt occurs.
+ */
+void intRadio(void) {
+ irqFlags1 = regRead(IRQ_FLAGS1);
+ irqFlags2 = regRead(IRQ_FLAGS2);
+}
+
+void timeRadio(void) {
+ if (timeoutEnabled && timeoutInts++ >= TIMEOUT_INTS) {
+ timeoutEnable(false);
+ timeout();
+ }
+}
+
+void sleepRadio(void) {
+ setMode(MODE_SLEEP);
+}
+
+void wakeRadio(void) {
+ setMode(MODE_STDBY);
+ // should better wait for ModeReady irq?
+ _delay_ms(5);
+}
+
+void setNodeAddress(uint8_t address) {
+ regWrite(NODE_ADDR, address);
+}
+
+uint8_t getRssi(void) {
+ return regRead(RSSI_VALUE);
+}
+
+void setOutputPower(uint8_t rssi) {
+ uint8_t pa = 0x40; // -18 dBm with PA1
+ // adjust power from -2 to +13 dBm
+ pa += min(max(rssi - 69, PA_MIN), PA_MAX);
+ regWrite(PA_LEVEL, pa);
+}
+
+uint8_t getOutputPower(void) {
+ return regRead(PA_LEVEL);
+}
+
+void startReceive(void) {
+ // get "PayloadReady" on DIO0
+ regWrite(DIO_MAP1, 0x40);
+
+ setMode(MODE_RX);
+}
+
+PayloadFlags payloadReady(void) {
+ PayloadFlags flags = {.ready = false, .crc = false};
+ if (irqFlags2 & (1 << 2)) {
+ flags.ready = true;
+ flags.crc = irqFlags2 & (1 << 1);
+ clearIrqFlags();
+ setMode(MODE_STDBY);
+ }
+
+ return flags;
+}
+
+size_t readPayload(uint8_t *payload, size_t size) {
+ size_t len = regRead(FIFO);
+ len = min(len, size);
+
+ // TODO assume and ignore address for now
+ regRead(FIFO);
+
+ spiSel();
+ transmit(FIFO);
+ for (size_t i = 0; i < len; i++) {
+ payload[i] = transmit(FIFO);
+ }
+ spiDes();
+
+ return len;
+}
+
+size_t receivePayload(uint8_t *payload, size_t size, bool timeout) {
+ timeoutEnable(timeout);
+ startReceive();
+
+ // wait until "PayloadReady" or timeout
+ do {} while (!(irqFlags2 & (1 << 2)) && !(irqFlags1 & (1 << 2)));
+ bool ready = irqFlags2 & (1 << 2);
+ bool timedout = irqFlags1 & (1 << 2);
+
+ clearIrqFlags();
+ if (ready) {
+ timeoutEnable(false);
+ }
+ setMode(MODE_STDBY);
+
+ if (timedout) {
+ // full power as last resort
+ regWrite(PA_LEVEL, 0x5f);
+
+ return 0;
+ }
+
+ return readPayload(payload, size);
+}
+
+size_t transmitPayload(uint8_t *payload, size_t size, uint8_t node) {
+ // message + address byte
+ size_t len = min(size, MESSAGE_SIZE) + 1;
+
+ spiSel();
+ transmit(FIFO | 0x80);
+ transmit(len);
+ transmit(node);
+ for (size_t i = 0; i < size; i++) {
+ transmit(payload[i]);
+ }
+ spiDes();
+
+ // get "PacketSent" on DIO0 (default)
+ regWrite(DIO_MAP1, 0x00);
+
+ setMode(MODE_TX);
+
+ loop_until_bit_is_set(irqFlags2, 3);
+ clearIrqFlags();
+
+ setMode(MODE_STDBY);
+
+ return len;
+}
diff --git a/librfm.d b/librfm.d
new file mode 100644
index 0000000..cfec903
--- /dev/null
+++ b/librfm.d
@@ -0,0 +1,6 @@
+librfm.d: librfm.c librfm.h pins.h types.h spi.h utils.h
+librfm.h:
+pins.h:
+types.h:
+spi.h:
+utils.h:
diff --git a/librfm.h b/librfm.h
new file mode 100644
index 0000000..dda6da7
--- /dev/null
+++ b/librfm.h
@@ -0,0 +1,189 @@
+/*
+ * File: librfm.h
+ * Author: torsten.roemer@luniks.net
+ *
+ * Created on 23. März 2025, 23:04
+ */
+
+#ifndef LIBRFM_H
+#define LIBRFM_H
+
+#include
+#include
+
+#include "pins.h"
+#include "types.h"
+#include "spi.h"
+#include "utils.h"
+
+#define FIFO 0x00
+#define OP_MODE 0x01
+#define DATA_MOD 0x02
+#define BITRATE_MSB 0x03
+#define BITRATE_LSB 0x04
+#define FDEV_MSB 0x05
+#define FDEV_LSB 0x06
+#define FRF_MSB 0x07
+#define FRF_MID 0x08
+#define FRF_LSB 0x09
+#define OSC1 0x0a
+#define PA_LEVEL 0x11
+#define LNA 0x18
+#define RX_BW 0x19
+#define AFC_FEI 0x1e
+#define AFC_BW 0x20
+#define RSSI_CONFIG 0x23
+#define RSSI_VALUE 0x24
+#define DIO_MAP1 0x25
+#define DIO_MAP2 0x26
+#define IRQ_FLAGS1 0x27
+#define RSSI_THRESH 0x29
+#define RX_TIMEOUT1 0x2a
+#define RX_TIMEOUT2 0x2b
+#define PREAMB_MSB 0x2c
+#define PREAMB_LSB 0x2d
+#define IRQ_FLAGS2 0x28
+#define SYNC_CONF 0x2e
+#define SYNC_VAL1 0x2f
+#define SYNC_VAL2 0x30
+#define SYNC_VAL3 0x31
+#define SYNC_VAL4 0x32
+#define SYNC_VAL5 0x33
+#define SYNC_VAL6 0x34
+#define SYNC_VAL7 0x35
+#define SYNC_VAL8 0x36
+#define PCK_CFG1 0x37
+#define PAYLOAD_LEN 0x38
+#define NODE_ADDR 0x39
+#define CAST_ADDR 0x3a
+#define AUTO_MODES 0x3b
+#define FIFO_THRESH 0x3c
+#define PCK_CFG2 0x3d
+#define TEST_LNA 0x58
+#define TEST_PA1 0x5a
+#define TEST_PA2 0x5c
+#define TEST_DAGC 0x6f
+#define TEST_AFC 0x71
+
+#define MASK_MODE 0x1c
+
+#define MODE_SLEEP 0x00
+#define MODE_STDBY 0x04
+#define MODE_FS 0x08
+#define MODE_TX 0x0c
+#define MODE_RX 0x10
+
+#define PA_MIN 16
+#define PA_MAX 31
+
+#define MESSAGE_SIZE 63
+#define F_STEP 6103515625ULL
+#define CAST_ADDRESS 0x84
+
+#define TIMEOUT_INTS 3 // about 100 milliseconds @ 30 Hz
+#define MAX_TIMEOUTS 9 // slow down tx attempts after so many timeouts
+
+/**
+ * Initializes the radio module with the given carrier frequency in kilohertz
+ * and node address.
+ */
+void initRadio(uint64_t freq, uint8_t node);
+
+/**
+ * Should be called when a radio interrupt occurred, i.e. 'PayloadReady'.
+ */
+void intRadio(void);
+
+/**
+ * Gives a timer pulse to the radio. Used to time-out blocking functions,
+ * i.e. transmitter waiting for a response from the receiver.
+ * TIMEOUT_INTS must be adjusted according to the frequency with that
+ * this function is called.
+ */
+void timeRadio(void);
+
+/**
+ * Shuts down the radio.
+ */
+void sleepRadio(void);
+
+/**
+ * Wakes up the radio.
+ */
+void wakeRadio(void);
+
+/**
+ * Sets the node address.
+ *
+ * @param address
+ */
+void setNodeAddress(uint8_t address);
+
+/**
+ * Returns the current RSSI value.
+ *
+ * @return rssi value
+ */
+uint8_t getRssi(void);
+
+/**
+ * Sets the output power based on the given receiver RSSI.
+ *
+ * @param rssi
+ */
+void setOutputPower(uint8_t rssi);
+
+/**
+ * Returns the current output power setting.
+ *
+ * @return ouput power
+ */
+uint8_t getOutputPower(void);
+
+/**
+ * Sets the radio to receive mode and maps "PayloadReady" to DIO0.
+ */
+void startReceive(void);
+
+/**
+ * Returns true if a "PayloadReady" interrupt arrived and clears the
+ * interrupt state.
+ *
+ * @return true if "PayloadReady"
+ */
+PayloadFlags payloadReady(void);
+
+/**
+ * Sets the radio in standby mode, puts the payload into the given array
+ * with the given size, and returns the length of the payload.
+ *
+ * @param payload buffer for payload
+ * @param size of payload buffer
+ * @return payload bytes actually received
+ */
+size_t readPayload(uint8_t *payload, size_t size);
+
+/**
+ * Waits for "PayloadReady", puts the payload into the given array with the
+ * given size, and returns the length of the payload, or 0 if a timeout
+ * occurred.
+ *
+ * @param payload buffer for payload
+ * @param size of payload buffer
+ * @param timeout enable timeout
+ * @return payload bytes actually received
+ */
+size_t receivePayload(uint8_t *payload, size_t size, bool timeout);
+
+/**
+ * Transmits up to 64 bytes of the given payload with the given node address.
+ *
+ * @param payload to be sent
+ * @param size of payload
+ * @param node address
+ * @return payload bytes actually sent
+ */
+size_t transmitPayload(uint8_t *payload, size_t size, uint8_t node);
+
+#endif /* LIBRFM_H */
+
diff --git a/librfm.o b/librfm.o
new file mode 100644
index 0000000..820f521
--- /dev/null
+++ b/librfm.o
Binary files differ
diff --git a/nbproject/configurations.xml b/nbproject/configurations.xml
new file mode 100644
index 0000000..61fa6c1
--- /dev/null
+++ b/nbproject/configurations.xml
@@ -0,0 +1,45 @@
+
+
+
+
+ librfm.c
+
+
+ /home/dode/dev/librfm/Makefile
+ /home/dode/dev/librfm/nbproject/private/launcher.properties
+
+
+ ^(nbproject)$
+
+ /home/dode/dev/librfm
+
+ /home/dode/dev/librfm/Makefile
+
+
+
+ AVR|GNU
+ false
+ false
+
+
+
+
+
+ /home/dode/dev/librfm
+ ${MAKE} -f Makefile
+ ${MAKE} -f Makefile clean
+
+
+
+ .
+
+
+
+ -
+
+
+
+
diff --git a/nbproject/project.xml b/nbproject/project.xml
new file mode 100644
index 0000000..94e0375
--- /dev/null
+++ b/nbproject/project.xml
@@ -0,0 +1,26 @@
+
+
+ org.netbeans.modules.cnd.makeproject
+
+
+ librfm
+ c
+
+ h
+ UTF-8
+
+
+ /home/dode/dev/librfm
+
+
+
+ Default
+ 0
+
+
+
+ false
+
+
+
+
diff --git a/pins.h b/pins.h
new file mode 100644
index 0000000..c8cf6ce
--- /dev/null
+++ b/pins.h
@@ -0,0 +1,48 @@
+/*
+ * File: pins.h
+ * Author: torsten.roemer@luniks.net
+ *
+ * Created on 1. April 2023, 19:25
+ */
+
+#ifndef PINS_H
+#define PINS_H
+
+#include
+
+/* SPI */
+#define DDR_SPI DDRB
+#define PORT_SPI PORTB
+#define PIN_SS PB2
+#define PIN_MOSI PB3
+#define PIN_MISO PB4
+#define PIN_SCK PB5
+
+/* I2C */
+#define DDR_I2C DDRC
+#define PORT_I2C PORTC
+#define PIN_SCL PC5
+#define PIN_SDA PC4
+
+/* Radio Int */
+#define PIN_RINT PD2 // radio interrupt
+
+/* Radio SPI */
+#define DDR_RFM DDRB
+#define PORT_RFM PORTB
+#define PIN_RCS PB1 // radio chip select
+#define PIN_RRST PB0 // radio reset
+
+/* SD Card */
+#define DDR_SDC DDRD
+#define PORT_SDC PORTD
+#define PIN_SDCS PD4 // sdcard chip select
+
+/* Display */
+#define DDR_DISP DDRD
+#define PORT_DISP PORTD
+#define PIN_DCS PD5 // display chip select
+#define PIN_DDC PD6 // display data/command
+#define PIN_DRST PD7 // display reset
+
+#endif /* PINS_H */
diff --git a/spi.h b/spi.h
new file mode 100644
index 0000000..e9c3f66
--- /dev/null
+++ b/spi.h
@@ -0,0 +1,33 @@
+/*
+ * File: spi.h
+ * Author: torsten.roemer@luniks.net
+ *
+ * Created on 1. April 2023, 19:12
+ */
+
+#ifndef SPI_H
+#define SPI_H
+
+#include
+#include
+#include "pins.h"
+
+/**
+ * Sets slow SPI speed.
+ */
+void spiSlow(void);
+
+/**
+ * Sets fast SPI speed.
+ */
+void spiFast(void);
+
+/**
+ * Transmits the given byte and returns the byte reveived at the same time.
+ * @param data byte to be written
+ * @return byte read while writing
+ */
+uint8_t transmit(uint8_t data);
+
+#endif /* SPI_H */
+
diff --git a/types.h b/types.h
new file mode 100644
index 0000000..f15e271
--- /dev/null
+++ b/types.h
@@ -0,0 +1,69 @@
+/*
+ * File: types.h
+ * Author: torsten.roemer@luniks.net
+ *
+ * Created on 17. September 2023, 20:33
+ */
+
+#ifndef TYPES_H
+#define TYPES_H
+
+#include
+#include
+
+/* Width, height and color space of bitmaps and glyphs */
+typedef uint16_t width_t;
+typedef uint16_t height_t;
+typedef uint8_t space_t;
+
+/* Width * height * bytes per pixel */
+typedef uint32_t bytes_t;
+
+/* X and Y coordinates of the display */
+typedef uint16_t x_t;
+typedef uint16_t y_t;
+
+/* Char code (like UTF-8 code point) */
+typedef uint8_t code_t;
+
+/* Number of glyphs of a font */
+typedef uint8_t length_t;
+
+/**
+ * A point with its x and y coordinates.
+ */
+typedef struct {
+ int16_t x;
+ int16_t y;
+} Point;
+
+/**
+ * Flags for "payload ready" event.
+ */
+typedef struct {
+ bool ready;
+ bool crc;
+} PayloadFlags;
+
+/**
+ * Temperature read from transmitter including
+ * additional information.
+ */
+typedef struct {
+ uint16_t raw;
+ uint8_t power;
+} Temperature;
+
+/**
+ * Pointer to a function that takes no argument and returns void.
+ */
+typedef void (*Function)(void);
+
+/**
+ * Pointer to a function that takes an array of bytes
+ * and returns a boolean.
+ */
+typedef bool (*Consumer)(uint8_t*);
+
+#endif /* TYPES_H */
+
diff --git a/utils.h b/utils.h
new file mode 100644
index 0000000..8c0a340
--- /dev/null
+++ b/utils.h
@@ -0,0 +1,51 @@
+/*
+ * File: utils.h
+ * Author: torsten.roemer@luniks.net
+ *
+ * Created on 07. February 2025, 00:25
+ */
+
+#ifndef UTILS_H
+#define UTILS_H
+
+/**
+ * Computes the length of the given array.
+ */
+#define array_length(array) (sizeof(array) / sizeof(array[0]))
+
+/**
+ * Returns the greater of both given numbers.
+ * https://stackoverflow.com/questions/3437404/min-and-max-in-c
+ */
+#define max(a, b) \
+({ \
+ __typeof__ (a) _a = (a); \
+ __typeof__ (b) _b = (b); \
+ _a > _b ? _a : _b; \
+})
+
+/**
+ * Returns the smaller of both given numbers.
+ * https://stackoverflow.com/questions/3437404/min-and-max-in-c
+ */
+#define min(a, b) \
+({ \
+ __typeof__ (a) _a = (a); \
+ __typeof__ (b) _b = (b); \
+ _a < _b ? _a : _b; \
+})
+
+/**
+ * Divides the given numerator by the given denominator,
+ * rounds to the nearest int and returns it.
+ * http://stackoverflow.com/a/18067292/709426
+ */
+#define divRoundNearest(num, den) \
+({ \
+ ((num < 0) ^ (den < 0)) ? \
+ ((num - den / 2) / den) : \
+ ((num + den / 2) / den); \
+})
+
+#endif /* UTILS_H */
+